Dental apparatus



April 7, 1931.

P, MANTERNA'CH' DENTAL APPARATUS Filed July 9, 1929 2 Sheets-Sheet 1 1 NVEN TOR.

A TTORNE Y.

April 7, 193 P. MANTERNACH DENTAL APPARATUS Filed July 9. 1929 2Sheets-Sheet 2 I N VEN TOR.

A TTORNE Y.

Patented Apr. 7, 1931 PATENT OFFICE PAUL MANTERNACH, OF ST. PAUL,MINNESOTA DENTAL APPARATUS 9 Application filed July 9, 1929. Serial No.376,975.

i is

The present invention relates to improvements in dental apparatus andhas reference more particularly to a device for use in eliminating thewax from the mold by the action of heat. 7

One of the important objects of the present invention is to provide adental apparatus that includes an electric furnace or muflle mountedupon a suitable base and within which furnace or muffle is adapted to beremovably positioned, the flask or mold containing the wax pattern thatis used by dentists in castin bridgework inlays.

A further 0 ject is to provide a dental apparatus of the above-mentionedcharacter wherein an ejector unit is operatively associated with thefurnace for submitting the ready and easy ejection of the flask or moldfrom the furnace or muflie after the wax pattern has been eliminated.

' Another important object of the invention resides in'the provision ofa dental apparatus of the above-mentioned character which will expeditethe work in preparing inlays I and this in a positive and eflicientmanner,

the parts of the device embodying my invention being so arranged as topermit the same to be readily and easily assembled or, disassembled.

-A still further object is to provide a dental apparatus of theabove-mentioned character which is simple in construction, inexpensive,strong and durable and further well adapted for the purposes for whichit is designed.

Other objects and advantages of the inven' tion will become apparentfrom the following description when taken in connection with theaccompanying drawings.

In the accompanying drawings wherein like reference characters indicatecorresponding parts throughout the same;

Figure 1 is a top plan view of the dental apparatusembodying myinvention, a portion of the furnace or mufile being shown in section.

Figure 2 is a side elevation of the apparatus, a portlon of the basebeing shown in sectlon to more clearly disclose the mounting for theelectric switch.

. the edges thereof being disposed downwardly to provide side and endflanges. The corner portions of the flanges are constructed to formsupporting feet 2 thereby to space the base 1 from the surface asclearly shownin Figures 2 and 4 of the drawings.

Mounted on the base 1 at one end thereof is the electric heating furnaceor muffl'e denoted generally by the numeral 3. This heater embodiesinner and outer spaced metallic shells 4 and 5 respectively havingflanged top and bottom cap members 6 and 7 associated therewith.Aheating coil 8 consisting of spirally wound nichrome wire encircles theinner shell 4t and is maintained out of contact with the inner shell 4through the medium of the insulating material 9 which may be mica.Mineral wool, denoted by the numeral 11 fills the space between theheating coil and the outer shell 5 as is clearly indicated in Figures 1and 4 of the drawings.

Suitable bolts 12 extend through the top and bottom cap members 6 and 7,the heads of the bolts engaging with the upper face of the top cap 6while the threaded ends of these bolts extend through aperturedprotuberances 13 that extend upwardly from the base 1 for engagementwith the bottom face of the bottom cap 7 to space the heating furnace 3from the base. Suitable nuts 14 are threaded .on the lower ends of thebolts for engagement with the bottom face of the base 1 as shown veryclearly in Figure 4:.

Current is supplied to the heating coil 8 from any suitable source andthe lead in wires are shown at 15, the same carrying at their free endsthe quick detachable plug 16 that is of the conventional constructionfor association with a wall socket or the like (not shown).

A snap switch 17 also of any conventional construction is mounted on thebase 1 for association with the wiring 15 to control the turning on andoff of the current to the heating coil 8 and this switch unit isdetachably mounted on the base 1 in the manner as shown at 18 in Figure2.

The base 1 is formed with a circular opening 19 directly beneath theopen central portion of the heater 3 and extending vertically throughthe opening 19 for movement through the central portion of the heater 3is the tubular standard 20 that carries at its upper end, the mold orflask supporting spider 21, the ends of the arms thereof terminating inslight spaced relation with respect to the inner shell 4:.

The lower end of the standard 20 is slit to accommodate the forward endof the longitudinally extending lever or arm 22. This lever or arm ispivotally connected with the lower end of the tubular standard 20 as at23. The intermediate portion of the arm or lever 22 is disposed betweena pair of depending guides 24 that are secured at their upper edgeportions to the under side of the base 1 and the lever or arm ispivotally mounted adjacent its rear end at the rear end portion of theseguides as at 25. The actuating means for the lever 22 comprises a fingeroperated pin 26 that extends through a suitable opening provided in therear end portion of the base 1. This pin is also operable within aninverted U-shaped bracket 27 that is secured on the base 1 over theopening 28 and the upper end portion of the pin 26 is operable throughan opening formed in the crown portion of this bracket 27. A flange 29is formed on the intermediate portion of the pin 26 to preventdisplacement of said pin. The lower end of the pin rests on the upperface of the rear end portion of the pivoted lever or arm 22 and a screw30 is threaded through a transverse opening formed in the rear extremityof the lever arm 22 for engagement with the under side of the adjacentportion of the base 1 whereby the limit of the downward movement of thestandard 20 and the spider 21 supported on the upper end thereof may belimited.

The operation of my improved dental apparatus is thought to be readilyobvious from the construction disclosed and it is apparent that when themold or flask containing the wax pattern is placed in the electricheater 3, and the switch 17 is turned on, the heating coil 8 willdissolve the wax in the mold employed in the preparation of models orinvestments for inlays. The surplus moisture in the investment will beevaporated out slowly and the wax pattern dissolved and absorbed in theinvestment or evaporated by the application of heat to the mold orflask.

By pressing the pin 26 downwardly, the lever or arm 22 will be actuatedwhereby to raise the standard 20 and the spider 21 carried on the upperend thereof upwardly through the shell 4 so as to eject the mold orflask from the furnace.

When pressure on the pin 26 is released, the weight of the spider andsupporting standard will automatically return the movable parts to theirnormal positions as shown in Fig ure 4.

It will thus be seen from the foregoing description, that I haveprovided a dental apparatus that will expedite the removal of the waxfrom the mold and at the same time provide a means for ejecting the moldfrom the furnace or muffle. The simplicity of my device enables the sameto be constructed at a very low cost and yet be strong and durable andfurther at all times positive and efficient in carrying out the purposesfor which it is designed.

WVhile I have shown the preferred embodiment of my invention, it is tobe understood that minor changes in the size, shape and arrangement ofparts may be resorted to without departing from the spirit of theinvention or the scope of the appended claims.

What I claim is:

1. A dental apparatus comprising in combination, a base, an electricheating furnace mounted thereon and adapted to receive a dental flask,and a flask ejector mechanism including a standard arranged for verticalmovement through the base and the bore of the heater, a flask engagingunit carried by the upper end of the standard, a lever pivotedintermediate its ends beneath the base, one end thereof beingoperatively connected with the lower end of the standard, and manuallyoperable means for the other end of the lever to raise the ejector unit,said last-mentioned means including a vertically movable pin mounted onthe base, the lower end thereof having engagement with the adjacent endof the pivoted lever.

2. A dental apparatus, comprising in combination, a base, an electricheating furnace mounted thereon and adapted to receive a dental flask,and a flask ejector mechanism including a standard arranged for verticalmovement through the base and the bore of the heater, a flask engagingunit carried by the upper end of the standard, a lever pivotedintermediate its ends beneath the base, one end thereof beingoperatively connected with the lower end of the standard, and manuallyoperable means for the other end of the lever to raise the ejector unit,said last-mentioned means including a vertically movable pin mounted onthe base, the lower end thereof having engagement with the adjacent endof the pivoted lever, and means carried by the last-mentioned end of thelever for cooperation with the base to limit the downward movement ofthe standard and the ejector element carried by the upper end thereof.

In testimony whereof I aflix my signature.

PAUL MANTERNACH.

